peters



gleiten gitane gtttnt @fitta JOHN L. LAY OF BUFFALO, NEW YORK, ASSIGNOR TO IIIMSELF AND H. O. PERRY, OF SAME PLACE.

Letters Pate-nt No. 66,976, dated July 23, 1867.

IMPROVEMENT IN STEAM ENGINES.

TO ALL WHOM IT MAY CONCERN:

13e it known that I, .IOIIN L. LAY, of the city of Buffalo, in the county. 0f Eric, and Stili@ 0f NCW York, have invented `certain new and useful improvements in Compound Engines; and I do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying dra\\.'ings,.making part of this specification, in which- Figure I is a central vertical section of my improvcmeuts.`

Figure 2 is a front elevation with the valve'and portion of the steam-chest removed to show the ports.

Figure 3 is a perspective -view of the valve detached, i

Lilie letters designate corresponding parts in all the figures.

,My improvements relate to that class of engines in which two cylinders, a high and a low-pressure, are combined, the exhaust steam from the former being v'employed to work the piston of the latter, and the steam being used expansively in both. The object is to dispense with the use et' a stulhng-box intermediate between the two cylinders when abutting, or in their proximate heads when they are arranged a short distance apart, and to provide a single valve that shall suffice for operating both cylinders- The invention consists, first, in the employment of a tube which is connected by a steam-tight joint with the intermediate head of the abutting cylinders, or with the head of the high-pressure cylinder proximate to the low-pressure when the two cylinders are separated, which tube extends through the low-pressure cylinder into the stuling-box in the opposite head, the tube fitting around the piston-rod, which reciprocates within. It further consists in the construction of a piston-valve, provided with three pistons, which fit and work within the valve-chest, in combination with thesevcral ports a b c d, and exhaust-chamber c, by which both cylinders are operated, substantially as hereinafter fully set forth.

In the drawings, A and B represent a high and a low-pressure cylinder, with the former arranged vertically beneath and concentric with the latter, abutting together, with a single intermediate head, C, for both, which is bolted to the top of a. suitable frame, D, which supports them. E and F are respectively the pistons of the high andlow-pressure cylinders, the former attached to rod G, which extends upward through both cylinders, and is fastened to the centre of cress-head P, while the latter is attached to two rods, Q Q, connecting with the end of the cross-head, as shown in tig. 2; and H is a tube or pipe (represented as screwed into the intermediate head C) extending upward into the stul'ling-box I in the top head of the upper and low-pressure cylinder. This tube is made sufficiently large to permit the unobstructed reeiprocations of thcpiston-rod G. This stuling-box I prevents the escape through it of the steam from the high-pressure cylinder. When the two cylinders are made separate and arranged a short distance apart, the `tube H is screwed into the inneror proximate head of the high-pressure cylinder, from whence it extends into and through the low-pressure cylinder, as before described. It is evident that this tube may bc arranged so as to extend through the high instead of the lowpressure cylinder, and operate effectively, although the former arrangement is to be preferred.

From the foregoing description it is,rcadily perceived that the use of the tube I dispenses with the-necessity of a, stuing-box in the intermediate head of the two cylinders, which is so ditlcult of access, and with two stuffing-boxes when the cylinders are arranged apart. The employment of it costs but little. It is readily applied, and-can with little difficulty be applied to old engines which are of the proper construction and arrangement.

J represents the steam-chest of Athe cylinder A, K the valve, consisting of the rod f, bywhich it is operated, to which are attached the three pistons g h z', which, in the reciprocations of the valve, alternately open and close the ports a b c d, as will be presently more particularly described. The ports a b lead respectively to thc`upper and lower ends of the high-pressure cylinder, and c Z to the upper and lower ends of the lowpressure cylinder, as shown, while the chamber e, formed between the ports ed, into which the latter alternately lopen, permits the escape of the exhaust steam therefrom into the passage m, which communicates with the external air or conducts to the condenser.

The operation of this part of my improvement is as follows: When the valve 1s in the position represented in lig. 1 the port I) is open, allowing the steam from the boiler to pass` to the bottom of the high-pressure cylinder,

while the port a is covered by the piston g. The ports a and I) respectively open alternately into eZ e, and a, now communicating with (Z, permits the steam from the upper end of the high-pressure cylinder to pass into the bottom of the low-pressure cylinder,` as represented by the arrows, while the piston z, which in this position closes the passage between d c, leaves the one between c e open, through which the e.;haust steam from the upper end of the low-pressure cylinder is permitted to escape into the passage m, and thence into the air or condenser, as above described. When the piston is at its opposite throw, it is obvious that the port a will he open and 6 covered, with a corresponding change in the other parts, causing the steam to reverse its direction, the exhaust from the lower end ofthe low-pressure cylinder now escaping through Ad into e, and thence into m, as before.

It is evident that my improvements are applicable to compound engines when the cylinders arenrranged horizontally, and will operato with equal eliiciency. The advantage of my improved valve is that a single one Vsuitlces for both cylinders, thereby saving the expense of one or more valves with the extra machinery required for loperatingthem. An engineproviderl with my improvements `also weighs less and occupies less space than others, which. is of much importance when employed for marine purposes.

That I claim as my invention is A 1. The employment of a tube, H, in combination with the piston-rod Gr and cylinders. A B of a high and low-pressure engine, substantially in the manner 'and for the purposes set forth.

2. I also claim the valve Il, consisting of the rod f und pistons. g L z', arranged with reference to the ports a Z1 c c2, and chamber e, substantially as specified.

3. I also claim lthe above-described valve, in combination with the high and low-pressure cylinders A B, provided with the tube H, the whole arranged and operating substantially as described.

In witness whereof I have hereunto signed my nameiu the presence of two subscribing witnesses.l

JOI-TN L. LAY.

Witnesses:

JAY HYATT, J. R. BRAKE. 

